Upper Respiratory Tract
Respiratory System – Structure and Function
Part
Pharynx
Structure
 Passageway
 Throat
Glottis
 Passageway
Epiglottis
 Located at top of trachea
 Flap
 Contains two folded
structures of vocal cords
 Flexible tube
 'windpipe'
 Semi-cartilaginous rings
for support
 Lined with mucus
 Branch from trachea
 Smaller passageways
 One enters each lung
 Lined with mucus
 Branched from bronchi
 Finer network of tubes
 Lined with mucus
 Grape-like cluster of tiny
sacs
 Kept moist
 70-90 m2 in humans
 Walls one-cell thick and
adjacent to capillary
network (circ. System)
 Layers of tissue
surrounding lungs
 Flexible membrane
 Two layers separated by
thin film of lubricating fluid
 Muscle region
Larynx
Trachea
Bronchi
Lower Respiratory Tract
Bronchioles
Alveoli
Pleura
Diaphragm
Function
 Connects mouth and nasal
cavity to larynx and
esophagus
 Opening of trachea – allows
air to flow to lungs
 Helps prevent food from
entering the trachea
 Houses vocal cords
 Passageway for air (from
mouth/nose to lungs)
 Air passageway
 Air passageway
 Site of gas exchange (with
circulatory system)
 Contains lungs, while still
allowing them to expand
and contract
 Separates thoracic cavity
(lung area) from abdominal
cavity)
 Assists with ventilation of
the lungs